Level winding device



Jan. 26, 1960 R. ow 2,922,599

LEVEL WINDING DEVICE Filed June 4, 1957 OF TRUNNION SLIDABLE SHEAVE llilrlln I 6 FIG. 3. FIG.4.

INVENTOR. R. P. BIGELOVI,

ATTORNEY.

United States Patent I This invention relates to level winding devices, and more particularly to devices for causing steel cable, such as a sand line used in well drilling, to spool up .evenly on a hoisting drum.

In the winding of any flexible line upon a reel or drum,

- there is a tendency for the line to wind unevenly. This vis Objectionable in that it may cause the line to jerk or tangle when it is unspooled. Various devices such as level winders on reels for fish line and traveling guides for use in winding thread on bobbins of sewing machines ,have been proposed to remedy this condition.

In winding steel cable upon a drum, it is important that I each layer extend-from flange to flange. portant that successive turns of any one layer lay up It is also imcloseto one another and yet not pile up on top of one another close to the flanges. It is diflicult to cause the successiveturns to lay up close to one another, especially in well drilling operations where variations in load cause changes in the twist of the cable. I 1 While devices have heretofore been proposed for solving the problem of properly winding steel cable on a .drum,-the general practice has been to place a'man near the drum in a position where he can use a piece of pipe,

, a wrench, a crow-bar or the like to guide the cable on to .the drum. This is, of course, hazardous.

Moreover, it requires considerable guesswork and skill to so manipulate atool as to cause cable to wind up properly on a drum.

Accordingly, it is an-object of the present invention to provide a level winding device which enables an operation to be performed upon a cable as it is being spooled up on a drum as the result of which it will coil up closely and evenly all across thecylindrical surface of the drum from one. flange to the other and yet not overlay or pile up adjacent the flanges. This is accomplished by providing a device which enables an operator to cause tension in the cable to place a slight lateral force or bias upon a sheave which is used to guide the cable on to the drum. The arrangement is such that the direction of the bias can be changed at will, so that as the direc- .tion of travel of the turns upon the drum is reversed, the guiding bias on the cable can be reversed. This is accomplished without the change in the angle with which the cable approaches the drum having any effect upon the amount ofthe bias, at least to any material extent.

Other objects and advantages of the invention will be apparent from a consideration of the following specification taken in connection with the accompanying drawings, in which:

Fig. l is a fragmentary perspective View of a drum and cable spooling mechanism with a level winding device constructed in accordance with the present invention applied thereto;

Fig. 2 is a perspective view of the shaft and sheave employed in the level winding device of Fig. l, the sheave being shown in cross-section;

Fig. 3 is a vertical cross-sectional view of a portion of a shaft constructed in accordance with the invention and illustrating one way in which it might be made;

2,922,599 Patented Jan. 26, 1960 ice frame 10 is there illustrated with a drum 11 mounted thereon. A suitable engine (not shown) may be used to rotate the drum, thus causing the cable 12 to be spooled upon it.

In-accordance with the present invention, a sheath 13 is mounted upon the shaft 14 so as to be nearly tangential to the cable 12. The sheave 13 can slide freely back and forth upon the shaft 14 throughout the width of any layer of cable 'upon the drum.

As illustrated, the shaft 14 is located in front of the drum 11 so that the cable 12 plays under the sheave 13 as it isfed upon the drum. The mounting means for the shaft 14 is such that its axis is approximately parallel to the axis of the drum 11. However, the mountingmeans is variable, so that the position of the shaft with respect to the frame 10 may be;cha nged slightly, and so that the angle the axis of the shaft" makes with the axis of the drum may be, changed slightly when desired.

i In the embodiment of the invention shown in Fig. 1, .the adjustment of'position'of the shaft is accomplished 'by .its special construction. .with: trunnions 16 which are fitted into bearings '15 of the frame '10. The trunnions 16 project diagonally from The shaft 14 is provided the ends of the shaft 14 at points spaced degrees apart on the cross-sectional circle of the shaft, as shown ;in Figure 2. The shaft 14 may be made of one piece of steel, as shown in Fig. 2, or it may be made by welding apiece of tubing on end plates 17, which are in turn welded to a trunnion shaft extending lengthwise therethrough, as illustrated in Figs. 3 and-4.

However constructed, the essential characteristic ofthe form of the invention of Fig. 1 is that the surface of the shaft 14 upon which the sheave 13 slides backand forth is eccentrically disposed with respect to the trunnions 16.

Thus, by simply rotating the shaft 14, and without imparting any side thrust to the sheave 13 other than that imparted to it by the cable 12 itself, a small force or bias .may be maintained on the sheave in a lateral direction opposite to the travel of the turns of the cable on the drum, and that this bias can be maintained withoutany material variation until an'entire layer of cable is spooled upon the drum. When one layer of cable on the drum is-completed, the next layer is, of course, wrapped upon it with the turns traveling in the opposite direction. This makes it necessary to reverse the direction of the bias on the sheave 13. Accordingly, some means is provided for rotating the shaft 14. One such means is illustrated in Fig. 1 as consisting of a worm and gear in a housing 18. This mechanism may be keyed to one of the trunnions 16 and provided with a control Wheel 20, so that by turning the control wheel the shaft 14 may be rotated.

Itwill be apparent that the mechanism in the housing 18 not only adjusts the position of the shaft 14 but that it positively holds it in an adjusted position regardless of the direction of the pull of the cable on the sheave 13. The adjusting mechanism is in no way responsive to the travel of the cable on the drum or to the particular location of a given turn of cable on the drum. It causes the cable to put a bias on the sheave 13, but the angle between the axis of the shaft 14 and the axis of the drum 11 remains constant during the wrapping of any given layer on the drum, so that the magnitude of the bias remains nearly constant during the wrapping of the entire layer.

3 Ordinarily, the shaft 14 will be rotated 180 degrees upon the completion of the wrapping of each layer of cable on the drum. However, it is obvious that the amount of bias on the sheave 13 can be controlled by varyingtlie exact angular position of the shaft 14, and as the successive layers of cable build up to larger diameters von the drum, the degrees'of rotation'of the shaft may be varied to alter the amount of the'b'ias.

Also, it should be mentioned that as such layer of cable is completed, it is desirable to have the first-turn of the next layer up close to the flange of the drum.

Hence, ordinarily, the shaft 14 should be rotated before thatparticular turn is 'layed. Thus, with the cable being fed upon the drum as illustrated in Fig. '1, the surface of theshaft 14 upon which the sheave 13 slides is closer -to the drum on the right hand side than on the left hand side, so that a bias to the right is placed upon the sheave by the tension in the cable. is being made to travel up-hill on the shaft to [the left, and this tends to hold each wrap of the cable on the drum up against the previous wrap. This condition will ordinarily be maintained until just before the last turn of that layer is completed. The shaft 14 should then "be turned 180 degrees to cause the last wrap of that layer and'thefirst wrap of the next layer to lay up close to the flange of the drum.

However, depending on conditions beyond the control of the operator, cable sometimes tendsto pile up'several layers close to the flanges on a drum, which is, of course, not desirable. When such conditions exist, it is clear that bias away from the flange should'be maintained on the first wrap of each new layer. This can readily be accomplished with the device of the present invention by simply not rotating the shaft '14 until the first wrapof a new layer has been laid.

The device can, therefore, be operated to controlthe 'spoolingof a cable properly under varying conditions'and regardless of the changes in the diameter of the layers. In the arangement of Fig. 1, the axis of thesurface of the shaft 14 may be said to swing about an imaginary pivot point midway between the extremes of the surface over which the sheave 13 slides. That is, with the shaft in the position shown, the right end of the shaft is near the drum and the left end farther away, but there -is a point half way between the bearings 15,where the center line of-the eccentric surface crosses the center line of the trunnions 16, which always remains the same distance from the drum. It is about this pointthat the shaft '14 swings when the gear in the housing 18 is manipulated.

The provision of means for causing the shaft-14 to swing, about its midpoint is an important feature of the species of the invention shown in Fig. 1, since it means that there is a certain symmetry in the application of the biasing forces imparted. to the cable by the sheave 13 regardless of whether the particular Wrap of the cable on the drum is near one flange or the other or near the middle of the drum.

However, in its broader aspects, the invention is not limited to the provision of such mechanism as will cause the shaft to swing about its midpoint, and Fig. '5 illustrates a modification in which a shaft 21 is'employed In other words, the sheave be pivoted at 22 on a portion 25 of the frame.

4 near one end. Thus, it may A sheave 23 slides back and forth on the shaft 21 to guide and put a bias on the cable 24 in a manner similar to that explained above in connection with the device of Fig. 1 as the shaft 21 is moved and held in a desired angular position with respect to a drum by a connecting rod- 26 and a hydraulic power cylinder 27. Any suitable arrangement, such as the fluid lines 28 and control valve 29, with a handle 30, may be used to move a piston in the cylinder 27.

It is, of course, within the purview of the invention to use hydraulic. means like that illustrated in Fig. 5 instead of the gear of Fig. l to actuate and hold an eccentric shaft like that of Fig. 1. Also, an electric motor could be used to adjust and hold a shaft in the desired angular position.

Various otherchanges may be made without departing from the spirit of the invention or the scope of the annexed claims.

I claim:

1. As an article of manufacture, a shaft suitable for use in a level winding device, said shaft having a cylindrical surface upon which a sheave may slide back and forth and two trunnions, one on each end of the shaft, said surface being eccentrically disposed with respect to the trunnions and said trunnions being diagonally spaced degrees apart on said shaft whereby said surface will swing about an imaginary pivot point midway of its ends whenthe shaft is rotated on said trunnions.

2. In mechanism for spooling cable, the combination with a frame and a drum of a level winding device comprising a shaft, an arrangement for mounting the shaft onthe frame in front of the drum with its axis approximately parallel to the axis of the drum, said arrangement including bearings fixed to the frame and trunnions fixed to the shaft, there being one trunnion at each end of the shaft, the trunnions being in line with each other but eccentrically disposed with respect to the cylindrical surface of the shaft and spaced 180 apart on the shaft, means for rotating the trunnions in the bearings thereby changing the angle .of the axis of the shaft slightly with respect to the axis of the drum, a

which swings about a point sheave rotatably mounted on the shaft and so arranged that it may slide back and forth on the shaft to guide the cable as it is fed onto the drum to wrap a layer thereon, and control means for positively adjusting the means for rotating the trunnions, regardless of the direction of pull of the cable, thereby causing the cable to place a slight bias on the sheave and causing a layer dfthe cable on the drum to be properly wrapped.

References Cited in the file of this patent UNITED STATES PATENTS 86,098 Parker Jan. 19, 1869 1,396,649 Minshall Nov. 8, 1921 1,606,964 Sexauer Nov. 16, 1926 2,372,232 Thornburg Mar. 27, 1945 2,591,770 Benner Apr. 8, 1952 2,595,584 Jones May 6, 1952 2,855,163 Powers Oct. 7, 1958 

